U.S. patent application number 14/435216 was filed with the patent office on 2015-10-08 for production and use of new thermoplastic polyurethane elastomers based on polyether carbonate polyols.
The applicant listed for this patent is BAYER MATERIALSCIENCE AG. Invention is credited to Christoph Gurtler, Wolfgang Kaufhold, Christian Wamprecht.
Application Number | 20150284501 14/435216 |
Document ID | / |
Family ID | 49328530 |
Filed Date | 2015-10-08 |
United States Patent
Application |
20150284501 |
Kind Code |
A1 |
Wamprecht; Christian ; et
al. |
October 8, 2015 |
PRODUCTION AND USE OF NEW THERMOPLASTIC POLYURETHANE ELASTOMERS
BASED ON POLYETHER CARBONATE POLYOLS
Abstract
The invention relates to a method for producing a thermoplastic
polyurethane elastomer based on polyether carbonate polyols. The
method comprises a first step, in which at least A) an organic
diisocyanate and B) a polyol having a number-average molecular
weight Mn>=500 and <=5000 g/mol are reacted to form an
isocyanate-terminated prepolymer. In a second step, the prepolymer
is reacted with C) one or more chain extenders having a molecular
weight>=60 and <=490 g/mol and optionally D) a monofunctional
chain stopper or E) an organic diisocyanate, wherein optionally at
least F) one catalyst is used in the first and/or second step.; The
molar ratio of the sum of the isocyanate groups from A) and, if
applicable, E) to the sum of the groups reactive to isocyanate in
B), C), and, if applicable, D) is >=0.9:1 and <=12:1, and
component B) contains at least one polyether carbonate polyol,
which can be obtained by adding carbon dioxide and alkylene oxides
to H-functional starter substances. The invention further relates
to a thermoplastic polyurethane elastomer produced in accordance
with the method according to the invention, the use of said
thermoplastic polyurethane elastomer to produce extruded or
injection molded items, and the items produced by extrusion or
injection molding.
Inventors: |
Wamprecht; Christian;
(Neuss, DE) ; Kaufhold; Wolfgang; (Koln, DE)
; Gurtler; Christoph; (Koln, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BAYER MATERIALSCIENCE AG |
Leverkusen |
|
DE |
|
|
Family ID: |
49328530 |
Appl. No.: |
14/435216 |
Filed: |
October 11, 2013 |
PCT Filed: |
October 11, 2013 |
PCT NO: |
PCT/EP2013/071243 |
371 Date: |
April 13, 2015 |
Current U.S.
Class: |
528/58 ;
264/328.1 |
Current CPC
Class: |
C08G 18/3206 20130101;
C08G 18/4837 20130101; C08G 18/4808 20130101; C08G 18/10 20130101;
C08G 18/10 20130101; C08G 18/12 20130101; C08G 18/34 20130101; C08G
18/12 20130101; C08G 2/12 20130101; C08G 18/44 20130101; C08G 2/12
20130101; C08G 18/10 20130101; C08G 18/12 20130101; C08G 18/12
20130101; C08G 18/10 20130101; C08G 18/36 20130101; C08G 18/36
20130101; C08G 18/34 20130101; C08G 18/38 20130101; C08G 18/3203
20130101; C08G 18/32 20130101; C08G 18/34 20130101; C08G 18/3203
20130101; C08G 18/12 20130101; C08G 18/4018 20130101; C08G 18/10
20130101; C08G 18/12 20130101; C08G 18/32 20130101; C08G 18/34
20130101; C08G 18/38 20130101; C08G 18/10 20130101; C08G 18/244
20130101; C08G 18/7671 20130101 |
International
Class: |
C08G 18/76 20060101
C08G018/76; C08G 18/24 20060101 C08G018/24; C08G 18/32 20060101
C08G018/32 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 16, 2012 |
DE |
10 2012 218 848.7 |
Claims
1.-17. (canceled)
18. A process for the production of a thermoplastic polyurethane
elastomer comprising reacting, in a first step, at least A) one
organic diisocyanate comprising two isocyanate groups with B) one
polyol with number-average molar mass M.sub.n.gtoreq.500 and
.ltoreq.5000 g/mol, which has two isocyanate-reactive groups, to
give an isocyanate-terminated prepolymer, and reacting, in a second
step, the prepolymer with C) one or more chain extenders with molar
mass .gtoreq.60 and .ltoreq.490 g/mol, which have two
isocyanate-reactive groups, and optionally D) a monofunctional
chain terminator which has an isocyanate-reactive group and/or
optionally E) an organic diisocyanate comprising two isocyanate
groups, where F) a catalyst is optionally used in the first and/or
second step, the molar ratio of the entirety of the isocyanate
groups from A) and optionally E) to the entirety of the
isocyanate-reactive groups in B), C), and optionally D) is
.gtoreq.0.9:1 and .ltoreq.1.2:1 and component B) comprises at least
one polyether carbonate polyol obtainable via an addition reaction
of carbon dioxide and alkylene oxides onto H-functional starter
substances.
19. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein in the second step the
prepolymer is reacted only with C) one or more chain extenders with
molar mass .gtoreq.60 and .ltoreq.490 g/mol, which have two
isocyanate-reactive groups, and optionally D) a monofunctional
chain terminator which has an isocyanate-reactive group and/or
optionally E) an organic diisocyanate comprising two isocyanate
groups.
20. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the polyether carbonate
polyol is obtainable via an addition reaction of carbon dioxide and
alkylene oxides onto H-functional starter substances with the use
of multimetal cyanide catalysts.
21. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the proportion of
ethylene oxide in the alkylene oxides is .gtoreq.0 and .ltoreq.90%
by weight.
22. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the content of carbonate
groups, calculated as CO.sub.2 in the polyether carbonate polyol is
.gtoreq.3 and .ltoreq.35% by weight.
23. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the number-average molar
mass M.sub.n of the polyether carbonate polyol is .gtoreq.500 and
.ltoreq.10000 g/mol.
24. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the average OH
functionality of the polyether carbonate polyol is .gtoreq.1.85 and
.ltoreq.2.5.
25. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the organic diisocyanate
A) comprises at least one aromatic diisocyanate.
26. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein component B) comprises at
least one polyether carbonate polyol and at least one polyether
polyol.
27. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein component B) comprises at
least one polyether carbonate polyol and at least one polyester
polyol.
28. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein component B) comprises at
least one polyether carbonate polyol and at least one polycarbonate
polyol.
29. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein component B) comprises
two polyether carbonate polyols that differ from one another.
30. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein component C) comprises
diols, diamines, or diol/diamine mixtures.
31. The process for the production of a thermoplastic polyurethane
elastomer as claimed in claim 18, wherein the reaction of the
components takes place in a reactive extruder or by the
mixing-head-belt process.
32. A thermoplastic polyurethane elastomer obtained by the process
as claimed in claim 18.
33. A method comprising utilizing the thermoplastic polyurethane
elastomer as claimed in claim 32 for the production of
injection-molded or extruded items.
34. An item obtained via injection molding or extrusion of the
thermoplastic polyurethane elastomer as claimed in claim 32.
Description
[0001] The invention relates to a process for the production of a
thermoplastic polyurethane elastomer based on polyether carbonate
polyols. The invention further relates to a thermoplastic
polyurethane elastomer produced by the process of the invention,
the use thereof for the production of extruded or injection-molded
items, and also the items produced via extrusion or injection
molding.
[0002] Thermoplastic polyurethane elastomers (TPUs) are of great
importance in industry because they have excellent mechanical
properties and can be processed by thermoplastic methods at low
cost. Their mechanical properties can be varied widely via the use
of different chemical structural components. Kunststoffe [plastics]
68 (1978), pp. 819-825 and Kautschuk, Gummi, Kunststoffe [Rubber,
Natural Rubber, Plastics] 35 (1982), pp. 568-584 provide overviews
of TPUs, and their properties and uses.
[0003] TPUs are composed of linear polyols, mostly polyester
polyols, polyether polyols, or polycarbonate polyols, organic
diisocyanates, and short-chain compounds having two
isocyanate-reactive groups (chain extenders). It is also possible
to add catalysts in order to accelerate the formative reaction. The
molar ratios of the structural components can be varied widely, and
by this means it is possible to adjust the properties of the
products. Products obtained have a wide range of Shore hardness,
depending on the molar ratios of polyols to chain extenders. The
thermoplastically processible polyurethane elastomers can be
constructed either stepwise (prepolymer process) or via
simultaneous reaction of all of the components in one stage
(one-shot process). The prepolymer process begins by producing an
isocyanate-containing prepolymer from the polyol and the
diisocyanate, and in a second step this is reacted with the chain
extender. The TPUs can be produced continuously or batchwise. The
best-known industrial production processes are the belt process and
the extruder process.
[0004] TPUs based on polyethylene oxide polyols and/or on
polypropylene oxide polyols (C2 and, respectively, C3 polyether
polyols) can be produced via polymerization of ethylene oxide
and/or propylene oxide by known processes with KOH catalysis or
multimetal cyanide catalysis DMC catalysis), and feature a good
overall property profile. Particular mention may be made of rapid
solidification after injection molding, and also very good
hydrolysis resistance and microbial resistance of the resultant
manufactured components. These TPU materials require improvement in
respect of mechanical properties, e.g. tensile strength, tensile
strain value, and abrasion resistance, and also thermal properties,
e.g. heat resistance. These improvements have hitherto been
achieved by way of example via the use of polyester polyols,
polycarbonate polyols, or C4-polyether polyols (polytetramethylene
glycols). However, the two last-mentioned polymeric polyols have a
complicated production process and are composed to some extent of
expensive starting materials, and are therefore also markedly more
expensive than C2- or C3-polyether polyols. Polyester polyols have
the disadvantage of susceptibility to hydrolysis.
[0005] DE 10147711 A describes a process for the production of
polyether alcohols made of oxirane compounds in the presence of DMC
catalysts and of a moderator gas, e.g. carbon dioxide, carbon
monoxide, hydrogen, and dinitrogen oxide. The low pressures used
during the synthesis lead to maximal incorporation of CO.sub.2 of
20 mol %, and the number of carbonate units present in the
polyether polyols is therefore very small. The resultant polyether
polyols can also be used for the production of thermoplastic
polyurethane elastomers, but the very small proportion of carbonate
units is unlikely to give any improvement of properties.
[0006] In J. Appl. Polym Sci. 2007, Vol. 104, pp. 3818-3826. S. Xu
and M Zhang describe the production of elastomers based on
polyethylene carbonate polyols which are produced via
copolymerization of ethylene oxide with CO.sub.2 in the presence of
a polymer-supported bimetal catalyst. The high proportion of units
resulting from ethylene oxide in the elastomer leads to highly
hydrophilic properties which make these materials unsuitable for
many application sectors.
[0007] WO2010/115567 A describes the production of microcellular
elastomers via reaction of an NCO-terminated prepolymer, produced
from an isocyanate and a first polyol, with a second polyol with a
number-average molar mass M.sub.n of from 1000 to 10 000 g/mol and
a chain extender with a molar mass below 800 g/mol. The
microcellular structure is generated via the use of chemical or
physical blowing agents, for example water. Polyols used can be
polyether carbonate polyols produced via copolymerization of
CO.sub.2 and alkylene oxides. Microcellular structures brought
about via the use of blowing agents are undesirable when TPUs are
processed in injection-molding machines and when extrusion
processes are used, because they give a lower level of mechanical
properties, in particular tensile strength and tensile strain at
break, and/or defects arise in the production of foils.
[0008] EP 1 707 586 A discloses the production of polyurethane
resins Which are based on polyether carbonate diols produced via
transesterification of carbonate esters, e.g. dimethyl carbonate,
with polyether diols having a molar mass below 500 g/mol. A
complicated, 2-stage synthesis is used to produce the products.
This lengthy transesterification process often leads to undesired
product discoloration and, because of side reactions (elimination
of water with formation of double bonds) to OH functionalities
<2 (mostly from 1.92 to 1.96), thus producing TPU products with
relatively low molecular weight. The level of mechanical properties
is then therefore also lower than for glycols with high OH
functionality (from 1.98 to 2.00).
[0009] It was therefore an object of the present invention to
provide a process for the production of low-cost thermoplastic
polyurethane elastomers which have a good overall property profile
and also a particularly high level of mechanical properties, and
are thus suitable for a wide range of applications. A particular
intention is that the TPUs produced have not only increased tensile
strength but also particularly low abrasion values and improved
heat resistance in comparison with the corresponding TPUs known
from the prior art, based on pure C2- or C3-polyether polyols, or
else based on the polyether carbonate diols known from the prior
art.
[0010] The invention achieves said object via a process for the
production of a thermoplastic polyurethane elastomer comprising
a first step in which at least [0011] A) one organic diisocyanate
comprising two isocyanate groups, [0012] B) one polyol with
number-average molar mass M.sub.n.gtoreq.500 and .ltoreq.5000
g/mol, which has two isocyanate-reactive groups, are reacted to
give an isocyanate-terminated prepolymer, and a second step in
which the prepolymer is reacted with [0013] C) one or more chain
extenders with molar mass .gtoreq.60 and .ltoreq.490 g/mol, which
have two isocyanate-reactive groups, [0014] and optionally [0015]
D) a monofunctional chain terminator which has an
isocyanate-reactive group and/or optionally [0016] E) an organic
diisocyanate comprising two isocyanate groups, where [0017] F) a
catalyst is optionally used in the first and/or second step, the
molar ratio of the entirety of the isocyanate groups from A) and
optionally E) to the entirety of the isocyanate-reactive groups in
B), C), and optionally D) is .ltoreq.0.9:1 and .ltoreq.1.2:1
[0018] and component B) comprises at least one polyether carbonate
polyol obtainable via an addition reaction of carbon dioxide and
alkylene oxides onto H-functional starter substances.
[0019] Surprisingly, it has been found that the TPUs produced by
the process of the invention have good mechanical properties. In
particular they are found to have higher tensile strength and
better thermal stability than corresponding TPUs based on pure C2-
or C3-polyether polyols, or else based on the polyether carbonate
diols known from the prior art. The TPUs produced in the invention
also retain very good elastic properties at low temperatures, since
no soft-segment crystallization occurs.
[0020] For the purposes of the invention, thermoplastic
polyurethane elastomers are elastomers which can be processed by a
thermoplastic route and Which comprise urethane units. These are
linear multiphase block copolymers composed of what are known as
hard and soft segments.
[0021] Hard segments are segments formed by the rigid blocks of the
copolymer, these being produced by reaction of short-chain chain
extenders and diisocyanates. These blocks have an ordered
arrangement, permitted via physical interaction with the
chain-extender blocks of the adjacent polymer chain. These
interactions provide the modes for the elastic properties. At the
same time, reversible disintegration of these modes on melting is
the precondition for the thermoplastic properties.
[0022] Reaction of the longer-chain polyol components with
diisocyanates produces flexible blocks in the copolymer which form
the soft segments, which have no ordered arrangement. These are
responsible for the chemical properties of the TPU, and also for
its low-temperature flexibility.
[0023] In one preferred embodiment of the invention, in the second
step the prepolymer is reacted only with [0024] C) one or more
chain extenders with molar mass .gtoreq.60 and .ltoreq.490 g/mol,
which have two isocyanate-reactive groups, and optionally [0025] D)
a monofunctional chain terminator which has an isocyanate-reactive
group and/or optionally [0026] E) an organic diisocyanate
comprising two isocyanate groups.
[0027] Organic diisocyanates A) that can be used are by way of
example diisocyanates described in Justus Liebigs Anna/en der
Chemie, 562, pp. 75-136.
[0028] Specific mention may be made of the following by way of
example:
[0029] Aromatic diisocyanates, for example tolylene
2,4-diisocyanate, tolylene 2,4-diisocyanateltolylene
2,6-diisocyanate mixtures, diphenylmethane 4,4'-diisocyanate,
diphenylmethane 2,4'-diisocyanate, and diphenylmethane
2,2-diisocyanate, diphenylmethane 2,4'-diisocyanate/diphenylmethane
4,4'-diisocyanate mixtures, urethane-modified liquid
diphenylmethane 4,4'-diisocyanates and diphenylmethane
2,4'-diisocyanates, 4,4'-diisocyanato-1,2-diphenylethane, and
naphthylene 1,5-diisocyanate. It is preferable to use, as aromatic
organic diisocyanates, diphenylmethane diisocyanate isomer mixtures
with >96% by weight content of diphenylmethane
4,4'-diisocyanate, and in particular diphenylmethane
4,4'-diisocyanate and naphthylene 1,5-diisocyanate. The
diisocyanates mentioned can be used individually or in the form of
mixtures with one another. They can also be used together with up
to 15% by weight (based on the total quantity of diisocyanate) of a
polyisocyanate, for example triphertylmethane
4,4',4''-triisocyanate or with polyphenyl polymethylene
polyisocyanates.
[0030] Other diisocyanates A) that can be used are aliphatic and
cycloaliphatic diisocyanates. Mention may be made by way of example
of hexamethylene diisocyanate, isophorone diisocyanate, cyclohexane
1,4-diisocyanate, 1-methylcyclohexane 2,4-diisocyanate, and
1-methylcyclohexane 2,6-diisocyanate, and also the corresponding
isomer mixtures, and dicyclohexylmethane 4,4'-, 2,4'-, and
2,2'-diisocyanate, and also the corresponding isomer mixtures. It
is preferable that the aliphatic organic diisocyanate used is
composed of at least 50% by weight of hexamethylene
1,6-diisocyanate, with preference 75% by weight, and particularly
preferably 100% by weight.
[0031] In one preferred embodiment of the invention, the organic
diisocyanate A) comprises at least one compound selected from the
group of aliphatic, aromatic, cycloaliphatic diisocyanates, and
particularly preferably at least one aliphatic and/or one aromatic
diisocyanate, very particularly preferably at least one aromatic
diisocyanate.
[0032] In the invention, component B) comprises at least one
polyether carbonate polyol obtainable via an addition reaction of
carbon dioxide and of alkylene oxides onto H-functional starter
substances. For the purposes of the invention "H-functional" means
a starter compound which has H atoms that are active in relation to
alkoxylation.
[0033] The production of polyether carbonate polyols via an
addition reaction of alkylene oxides and CO.sub.2 onto H-functional
starters is known by way of example from EP 0222453 A, WO
2008/013731 A. and EP 2115032 A.
[0034] In one preferred embodiment of the invention, the content of
carbonate groups, calculated as CO.sub.2 in the polyether carbonate
polyol is .gtoreq.3 and .ltoreq.35% by weight, preferably .gtoreq.5
and .ltoreq.30% by weight, particularly preferably .gtoreq.10 and
.ltoreq.28% by weight. The determination method is NMR, using the
analysis method specified in the section concerning experimental
methods.
[0035] In another preferred embodiment of the invention, the
number-average molar mass M.sub.n of the polyether carbonate polyol
is .gtoreq.500 and .ltoreq.10000 g/mol, preferably .gtoreq.500 and
.ltoreq.7500 g/mol, particularly preferably .gtoreq.750 and
.ltoreq.6000 g/mol and very particularly preferably .gtoreq.1000
and .ltoreq.5000 g/mol. The determination method is titration of
the terminal OH groups, using the analysis method specified in the
section concerning experimental methods under OH number
determination.
[0036] It is preferable that the average OH functionality of the
polyether carbonate polyol is .gtoreq.1.85 and .ltoreq.2.5,
preferably .gtoreq.1,9 and .ltoreq.2.3, particularly preferably
.gtoreq.1.95, and .ltoreq.2.1 and very particularly preferably
.gtoreq.1.97 and .ltoreq.2.03.
[0037] Production of the polyether carbonate polyols can generally
use alkylene oxides (epoxides) having from 2 to 24 carbon atoms.
Examples of the alkylene oxides having from 2 to 24 carbon atoms
are one or more compounds selected from the group consisting of
ethylene oxide, propylene oxide, 1-butene oxide, 2,3-butene oxide,
2-methyl-1,2-propene oxide (isobutene oxide), 1-pentene oxide,
2,3-pentene oxide, 2-methyl-1,2-butene oxide, 3-methyl-1,2-butene
oxide, 1-hexene oxide, 2,3-hexene oxide, 3,4-hexene oxide,
2-methyl-1,2-pentene oxide, 4-methyl-1,2-pentene oxide,
2-ethyl-1,2-butene oxide, 1-heptene oxide, 1-octene oxide, 1-nonene
oxide, 1-decene oxide, 1-undecene oxide, 1-dodecene oxide,
4-methyl-1,2-pentene oxide, butadiene monoxide, isoprene monoxide,
cyclopentene oxide, cyclohexene oxide, cycloheptene oxide,
cyclooctene oxide, styrene oxide, methylstyrene oxide, pinene
oxide, mono- or polyepoxidized fats in the form of mono-, di-, and
triglyceride, epoxidized fatty acids, C.sub.1-C.sub.24-esters of
epoxidized fatty acids, epichlorohydrin, glycidol, and derivatives
of glycidol, for example methyl glycidyl ether, ethyl glycidyl
ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, glycidyl
methacrylate, and also epoxy-functional alkoxysilanes, for example
3-glycidyloxypropyltrimethoxysilane,
3-glycidyloxypropyltriethoxysilane, 3-
glycidyloxypropyltripropoxysilane,
3-glycidyloxypropylmethyldimethoxysilane, 3
-glycidyloxypropylethyldiethoxysilane,
3-glycidyloxypropyltriisopropoxysilane. It is preferable to use, as
alkylene oxides, ethylene oxide and/or propylene oxide, in
particular propylene oxide.
[0038] In one particularly preferred embodiment of the invention,
the proportion of ethylene oxide in the entire quantity used of the
alkylene oxides is .gtoreq.0 and .ltoreq.90% by weight, preferably
.gtoreq.0 and .ltoreq.50% by weight, particularly preferably
.gtoreq.0 and .ltoreq.25% by weight.
[0039] Compounds having H atoms that are active in relation to
alkoxylation can be used as suitable H-functional starter
substance. Examples of groups that are active in relation to
alkoxylation, having active H atoms, are --OH, --NH.sub.2 (primary
amines), --NH-- (secondary amines), --SH, and --CO.sub.2H.
Preference is given to --OH and --NH.sub.2, particularly preference
being given to --OH. By way of example, one or more compounds
selected from the group consisting of polyhydric alcohols,
polyfunctional amines, polyfunctional thiols, amino alcohols, thio
alcohols, hydroxyesters, polyether polyols, polyester polyols,
polyester ether polyols, polyether carbonate polyols, polycarbonate
polyols, polycarbonates, polyethyleneimines, polyether amines (e.g.
those known as Jeffamine.RTM. from Huntsman), polytetrahydrofurans
(e.g. PolyTHF.RTM. from BASF, e.g. PolyTHF.RTM. 250, 650S, 1000,
1000S, 1400, 1800, 2000), polytetrahydrofuranamines (BASF product
polytetrahydrofuranamine 1700), polyether thiols, polyacrylate
polyols, castor oil, the mono- or diglyceride of ricinoleic acid,
monoglycerides of fatty acids, chemically modified mono-, di-
and/or triglycerides of fatty acids, and C.sub.1-C.sub.24 alkyl
fatty acid esters, where these comprise an average of at least two
OH groups per molecule, can be used as H-functional starter
substance, The C.sub.1-C.sub.4 alkyl fatty acid esters, where these
comprise an average of at least two OH groups per molecule, are by
way of example commercially available products such as Lupranol
Balance.RTM. (BASE AG), Merginol.RTM. grades (Hobum Oleochemicals
GmbH), Sovermol.RTM. grades (Cognis Deutschland GmbH & Co. KG),
and Soyol.RTM. grades (USSC Co.).
[0040] Examples of polyhydric alcohols suitable as H-functional
starter substances are dihydric alcohols, e.g. ethylene glycol,
diethylene glycol, propylene glycol, dipropylene glycol,
1,3-propanediol, 1,4-butanediol, 1,4-butenediol, 1,4-butynediol,
neopentyl glycol, 1,5-pentanediol, methylpentanediol (e.g.
3-methyl-1,5-pentanediol), 1.,6-hexanediol; 1,8-octanediol,
1,10-decanediol, 1,12-dodecanediol, bis(hydroxymethyl)cyclohexanes
(e.g. 1,4-bis(hydroxymethyl)cyclohexane), triethylene glycol,
tetraethylene glycol, polyethylene glycol, dipropylene glycol,
tripropylene glycol, polypropylene glycol, dibutylene glycol, and
polybutylene glycols, and also all of the modification products of
these abovementioned alcohols with various quantities of
.epsilon.-caprolactone. Mixtures of H-functional starters can also
use trihydric alcohols, for example trimethylolpropane, glycerol,
trishydroxyethyl isocyanurate, and castor oil.
[0041] The H-functional starter substances can also be selected
from the polyether polyols substance class, in particular those
with a number-average molar mass M.sub.n, in the range from 200 to
4000 g/mol, preferably from 250 to 2000 g/mol, Preference is given
to polyether polyols composed of repeating units of ethylene oxide
and of propylene oxide, preferably having a proportion of from 35
to 100% of propylene oxide units, particularly preferably having a
proportion of from 50 to 100% of propylene oxide units. These can
be random copolymers, gradient copolymers, or alternating or block
copolymers of ethylene oxide and propylene oxide. Examples of
suitable polyether polyols composed of repeating units of propylene
oxide and/or of ethylene oxide are the Desmophen.RTM.-,
Acclaim.RTM.-, Arcol.RTM.-, Baycoll.RTM.-, Bayfill.RTM.-,
Bayflex.RTM.-, Baygal.RTM.-, PET.RTM., and polyether polyols from
Bayer MaterialScience AG (e.g. Desmophen.RTM. 3600Z, Desmophen.RTM.
1900U, Acclaim.RTM. Polyol 2200, Acclaim.RTM. Polyol 40001,
Arcol.RTM. Polyol 1004, Arcol.RTM. Polyol 1010, Arcol.RTM. Polyol
1030, Arcol.RTM. Polyol 1070, Baycoll.RTM. BD 1110, Bayfill.RTM.
VPPU 0789, Baygal.RTM. K55, PET.RTM. 1004, Polyether.RTM. S180).
Examples of other suitable homopolyethylene oxides are the
Pluriol.RTM. E grades from BASF SE, and examples of suitable
homopolypropylene oxides are the Pluriol.RTM. P grades from BASF
SE, and examples of suitable mixed copolymers of ethylene oxide and
propylene oxide are the Pluronic.RTM. PE or Pluriol.RTM. RPE grades
from BASF SE.
[0042] The H-functional starter substances can also be selected
from the polyester polyols substance class, in particular those
with a number-average molar mass M.sub.n in the range from 200 to
4500 g/mol, preferably from 400 to 2500 g/mol. Polyester polyols
used comprise at least difunctional polyesters. Polyester polyols
are preferably composed of alternating acid units and alcohol
units. Examples of acid components used are succinic acid, maleic
acid, maleic anhydride, adipic acid, phthalic anhydride, phthalic
acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid,
tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and
mixtures of the acids and/or anhydrides mentioned. Examples of
alcohol components used are 1,2-ethanediol, 1,2-propanediol,
1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol,
1,6-hexanediol, 1,4-bis(hydroxymethyl)cyclohexane, diethylene
glycol, dipropylene glycol, trimethylolpropane, glycerol, and
mixtures of the alcohols mentioned. If dihydric or polyhydric
polyether polyols are used as alcohol component, polyester ether
polyols are thus obtained and can likewise serve as starter
substances for the production of the polyether carbonate polyols.
If polyether polyols are used for the production of the polyester
ether polyols, preference is given to polyether polyols with a
number-average molar mass M.sub.n of from 150 to 2000 g/mol.
[0043] Other H-functional starter substances that can be used are
polycarbonate polyols, for example polycarbonate diols, in
particular those with a number-average molar mass M.sub.n in the
range from 150 to 4500 g/mol, preferably from 500 to 2500 g/mol,
these being produced by way of example via reaction of phosgene,
dimethyl carbonate, diethyl carbonate, or diphenyl carbonate and
di- and/or polyhydric alcohols, or polyester polyols, or polyether
polyols. Examples of polycarbonate polyols are found by way of
example in EP 1359177 A. Poly-carbonate diols used can by way of
example comprise the Desmophen.RTM. C grades from Bayer
MaterialScience AG, e.g. Desmophen.RTM. C 1100 or Desmophen.RTM. C
2200.
[0044] Polyether carbonate polyols can likewise be used as
H-functional starter substances. In particular, polyether carbonate
polyols produced by the process described here are used. These
polyether carbonate polyols used as H-functional starter substances
are produced in advance for this purpose in a separate reaction
step.
[0045] The functionality (i.e. number of H atoms per molecule that
are active in relation to polymerization) of the H-functional
starter substances is generally from 1. to 4, preferably 2 or 3,
and particularly preferably 2. The H-functional starter substances
are used either individually or in the firm of mixture of at least
two H-functional starter substances.
[0046] Preferred H-functional starter substances are alcohols of
the general formula (I),
HO--(CH.sub.2).sub.x--OH (I)
where x is a number from 1 to 20, preferably an even number from 2
to 20. Examples of alcohols of formula (I) are ethylene glycol,
1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol,
and 1,12-dodecanediol. Other preferred H-functional starter
substances are neopentyl glycol, trimethylolpropane glycerol,
pentaerythritol, reaction products of the alcohols of formula (I)
with .epsilon.-caprolactone, e.g. reaction products of
trimethylolpropane with .epsilon.-caprolactone, reaction products
of glycerol with .epsilon.-caprolactone, and also reaction products
of pentaerythritol with .epsilon.-caprolactone. Preference is
further given to the following H-functional starter substances:
water, diethylene glycol, dipropylene glycol, castor oil, sorbitol,
and polyether polyols composed of repeating units of polyalkylene
oxides.
[0047] It is particularly preferable that the H-functional starter
substances are one or more compounds selected from the group
consisting of ethylene glycol, propylene glycol, 1,3-propanediol,
1,3-butanediol, 1,4-butanediol, 1,5-pentanediol,
2-methylpropane-1,3-diol, neopentyl glycol, 1,6-hexanediol
diethylene glycol, dipropylene glycol, glycerol,
trimethylolpropane, di- and trihydric polyether polyols, where the
polyether polyol is composed of a di- or tri-H-functional starter
substance and propylene oxide or of a di or tri-H-functional
starter substance, propylene oxide, and ethylene oxide. The
number-average molar mass M.sub.n of the polyether polyols is
preferably in the range from 62 to 4500 g/mol, and in particular in
the range from 62 to 3000 g/mol, very particularly preferably from
62 to 1500 g/mol. The functionality of the polyether polyols is
preferably from 2 to 3, particularly preferably 2.
[0048] In one preferred embodiment of the invention, the polyether
carbonate polyol is obtainable via an addition reaction of carbon
dioxide and of alkylene oxides onto H-functional starter substances
with the use of multimetal cyanide catalysts (DMC catalysts). The
production of polyether carbonate polyols via an addition reaction
of alkylene oxides and CO.sub.2 onto H-functional starters with the
use of DMC catalysts is disclosed by way of example in EP 0222453
A. WO 2008/013731 A. arid EP 21150:32 A.
[0049] DMC catalysts are in principle known from the prior art
relating to the homopolymerization of epoxides (see for example
U.S. Pat. No. 3,404,109 A, U.S. Pat. No. 3,829,505 A, U.S. Pat. No.
3,941,849 A, and U.S. Pat. No. 5,158,922 A). DMC catalysts
described by way of example in U.S. Pat. No. 5,470,813 A, EP 700
949 A, EP 743 093 A, EP 761 708 A, WO 97/40086 A, WO 98/16310 A and
WO 00/47649 A have very high activity in the homopolymerization of
epoxides, and permit the production of polyether polyols at very
low catalyst concentrations (25 ppm or less), The high-activity DMC
catalysts described in EP-A 700 949 are a typical example, and
comprise not only a double metal cyanide compound (e.g. zinc
hexacyanocobaltate(III)) and an organic ligand (e.g. tert-butanol),
but also a polyether with a number-average molar mass M.sub.n
greater than 500 g/mol.
[0050] The quantity used of the DMC catalyst is mostly smaller than
1% by weight, preferably smaller than 0.5% by weight, particularly
preferably smaller than 500 ppm, and in particular smaller than 300
ppm, based in each case on the weight of the polyether carbonate
polyol.
[0051] The polyether carbonate polyols are preferably produced in a
pressure reactor. One or more alkylene oxides, and the carbon
dioxide, are metered into the system after the optional drying of a
starter substance or of the mixture of a plurality of starter
substances, and the addition of the DMC catalyst, and also of the
additive(s), these being added in the form of solid or in the form
of a suspension before or after the drying process. In principle,
various methods can be used for the metering of one or more
alkylene oxides and of the carbon dioxide into the system. The
metering can be started in vacuo or at a preselected admission
pressure. It is preferable to set the admission pressure via
introduction of an inert gas, for example nitrogen, where the
pressure set is from 10 mbar to 5 bar, preferably from 100 mbar to
3 bar, and with preference from 500 mbar to 2 bar.
[0052] The metering of one or more alkylene oxides and of the
carbon dioxide into the system can take place simultaneously or
sequentially, and the entire quantity of carbon dioxide here can be
added all at once or metered into the system during the reaction
time. Preference is given to metering of the carbon dioxide into
the system. One or more alkylene oxides is/are metered into the
system simultaneously or sequentially in relation to the metering
of the carbon dioxide into the system. if a plurality of alkylene
oxides are used for the synthesis of the polyether carbonate
polyols, these can be metered into the system simultaneously or
sequentially by way of respective separate feeds, or by way of one
or more feeds where at least two alkylene oxides are metered in the
form of mixture into the system. It is possible to synthesize
random, alternating, block-type, or gradient-type polyether
carbonate polyols by varying the way in which the alkylene oxides
and the carbon dioxide are metered into the system.
[0053] It is preferable to use an excess of carbon dioxide, and in
particular the quantity of carbon dioxide is determined by way of
the total pressure under reaction conditions. An excess of carbon
dioxide is advantageous because carbon dioxide is unreactive. The
reaction has been found to produce the polyether carbonate polyols
at from 60 to 150.degree. C., preferably from 70 to 140.degree. C.,
particularly preferably from 80 to 130.degree. C., and at pressures
of from 0 to 100 bar, preferably from 1 to 90 bar, and particularly
preferably from 3 to 80 bar. At temperatures below 60.degree. C.,
the reaction ceases. At temperatures above 150.degree. C., the
quantity of undesired by-products increases sharply.
[0054] The proportion of polyether carbonate polyols, based on the
total mass of component B), is preferably .gtoreq.5 and
.ltoreq.100% by weight, particularly preferably .gtoreq.10 and
.ltoreq.100% by weight, and very particularly preferably .gtoreq.20
and .ltoreq.100% by weight. It is also possible that various
polyether carbonate polyols are present in component B).
[0055] It is also possible to use, as component B), mixtures of the
abovementioned polyether carbonate polyols with other linear
hydroxyl-terminated polyols with a number-average molar mass
M.sub.n of from 500 to 5000 g/mol, preferably from 750 to 4000
g/mol, and particularly preferably from 1000 to 3000 g/mol. By
virtue of the production process, these other polyols often
comprise small quantities of nonlinear compounds. An expression
therefore often used is "essentially linear polyols". Preferred
other polyols are polyester diols, polyether diols, polycarbonate
diols, and mixtures of these.
[0056] Suitable polyether diols can thus be produced by reacting
one or more alkylene oxides having from 2 to 4 carbon atoms in the
alkylene moiety with a starter molecule which comprises two active
hydrogen atoms. Examples that may be mentioned of alkylene oxides
are: ethylene oxide, 1,2-propylene oxide, epichlorohydrin, and
1,2-butylene oxide, and 2,3-butylene oxide, It is preferable to use
ethylene oxide, propylene oxide, and mixtures of 1,2-propylene
oxide and ethylene oxide. The alkylene oxides can be used
individually, in alternating succession, or in the form of
mixtures. Examples of starter molecules that can be used are:
water, amino alcohols, for example N-alkyldiethanolamines, for
example N-methyldiethanolamine, and diols, for example ethylene
glycol, 1,3-propylene glycol, 1,4-butanediol, and 1,6-hexanediol.
Mixtures of starter molecules can optionally also be used. Other
suitable polyether diols are the tetrahydrofuran polymerization
products containing hydroxyl groups. It is also possible to use
proportions of from 0 to 30%, based on the bifunctional polyethers,
of trifunctional polyethers, the quantity of these being however at
most that which produces a thermoplastically processible product.
The average molar masses M.sub.n of suitable polyether diols is
from 500 to 6000 g/mol, preferably from 750 to 4000 g/mol, and very
particularly preferably from 1000 to 3000 g/mol. They can be used
either individually or else in the form of mixtures with one
another.
[0057] Suitable polyester diols can by way of example be produced
from dicarboxylic acids having from 2 to 12 carbon atoms,
preferably having from 4 to 6 carbon atoms, and from polyhydric
alcohols. Examples of dicarboxylic acids that can be used are:
aliphatic dicarboxylic acids, for example succinic acid, maleic
acid, glutaric acid, adipic acid, suberic acid, azelaic acid, and
sebacic acid, and aromatic dicarboxylic acids, for example phthalic
acid, isophthalic acid, and terephthalic acid. The dicarboxylic
acids can be used individually or in the form of mixtures, e.g. in
the form of a succinic, glutaric, and adipic acid mixture. For the
production of the polyester diols it can optionally be advantageous
to use, instead of the dicarboxylic acids, the corresponding
dicarboxylic acid derivatives, for example carboxylic diesters
having from 1 to 4 carbon atoms in the alcohol moiety, carboxylic
anhydrides, or acyl chlorides. Examples of polyhydric alcohols are
glycols having from 2 to 10, preferably from 2 to 6, carbon atoms,
for example ethylene glycol, diethylene glycol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol,
1,12-dodecanediol, 2,2-dimethyl-1,3-propanediol, 1,3-propanediol,
and dipropylene glycol. The polyhydric alcohols can be used alone
or optionally in a mixture with one another, as required by the
desired properties. Other suitable compounds are esters of carbonic
acid with the diols mentioned, in particular those having from 4 to
6 carbon atoms, for example 1,4-butanediol or 1,6-hexanediol
condensates of hydroxycarboxylic acids, for example hydroxycaproic
acid, and polymerization products of lactones, for example
optionally substituted caprolactones. Preferred polyester diols
used are ethanediol polyadipates, 1,4-butanediolpolyadipates,
ethanediol 1,4-butanediol polyadipates, 1,6-hexanediol neopentyl
glycol polyadipates, 1,6-hexanediol 1,4-butanediol polyadipates,
and polycaprolactones. The number-average molar mass M.sub.n of the
polyester diols is from 500 to 5000 g/mol, preferably from 600 to
4000 g/mol, and particularly preferably from 800 to 3000 g/mol, and
they can be used individually or in the form of mixtures with one
another.
[0058] Chain extenders C) used can comprise tow-molecular-weight
compounds with a molar mass of .gtoreq.60 and .ltoreq.490 g/mol,
preferably .gtoreq.62 and .ltoreq.400 g/mol, and particularly
preferably .gtoreq.62 and .ltoreq.300 g/mol, where these have two
isocyanate-reactive groups.
[0059] In one preferred embodiment of the invention, the chain
extenders C) comprise, or consist of, diols, diamines, or
diol/diamine mixtures, however preferably diols.
[0060] Suitable chain extenders are diols such as ethanediol,
1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol, diethylene
glycol, dipropylene glycol, neopentyl glycol, diesters of
terephthalic acid with glycols having from 2 to 4 carbon atoms, for
example bis(ethylene glycol) terephthlate or bis(1,4-butanediol)
terephthlate, hydroxyalkylene ethers of hydroquinone, for example
1,4-di(hydroxyethyl)hydroquinone, and ethoxylated bisphenols, and
also reaction products of these with .epsilon.-caprolactone.
[0061] Preferred chains extenders are aliphatic diols having from 2
to 14 carbon atoms, for example ethanediol, 1.,3-propanediol,
1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol,
1,10-decanediol, 1,12-dodecanediol, diethylene glycol, dipropylene
glycol, neopentyl glycol, and 1 ,4-di(hydroxyethyl)hydroquinone.
Particular preference is given to the use of 1,3-propanediol,
1,4-butanediol, 1,6-hexanediol, and
1,4-di(hydroxyethyl)hydroquinone as chain extender.
[0062] Other suitable chain extenders are (cyclo)aliphatic
diamines, for example isophoronediamine, ethylenediamine,
1,2-propylenediamine, 1,3-propylenediamine,
N-methylpropylene-1,3-diamine, N,N'-dimethylethylenediamine, and
aromatic diamines, for example 2,4-tolylenediamine and
2,6-tolylenediamine, 3,5-diethyl-2,4-tolylenediamine, and
3,5-diethyl-2,6-tolylenediamine, and primary mono-, di-, tri-, or
tetraalkyl-substituted 4,4.degree. -diaminodiphenylmethanes.
[0063] Chain terminators D) that can be used are
low-molecular-weight compounds having an isocyanate-reactive group,
for example monoalcohols or monoamines. It is preferable to use at
least one compound selected from the group of 1-octanol, stearyl
alcohol, 1-butylamine, and stearylamine, and it is particularly
preferable to use 1-octanol.
[0064] Compounds suitable as other organic dilsocyanates E) are any
of the compounds mentioned for component A).
[0065] The TPUs can be produced by reacting quantities of the
structural components such that the molar ratio of the entirety of
the isocyanate groups from A) and optionally E) to the entirety of
the groups in B), C), and optionally D) reactive toward isocyanate
is from 0.9:1 to 1.2:1, preferably from 0.92:1 to 1.15:1, and
particularly preferably from 0.94 to 1.10:1.
[0066] The Shore hardness of the TPUs produced via the processes of
the invention can be varied widely, for example from Shore A 45 to
Shore D 90, via adjustment of the molar ratio of polyol B) to chain
extender C).
[0067] Suitable catalysts F) can optionally be used in the first
and/or second step of the process of the invention. The
conventional tertiary amines known from the prior art, e.g.
triethylamine, dimethylcyclohexylamine, N-methylmorpholine,
N,N'-dimethylpiperazine, 2-(dimethylaminoethoxy)ethanol,
diazabicyclo[2.2.2]octane, and also organometallic compounds, for
example titanium compounds, iron compounds, or tin compounds, for
example tin diacetate, tin dioctanoate, tin dilaurate, or the
dialkyltin salts of aliphatic carboxylic acids, for example
dibutyltin diacetate or dibutyltin dilaurate, are suitable
catalysts for the production of TPUs. Preferred catalysts are
organometallic compounds, in particular titanium compounds or iron
compounds or tin compounds.
[0068] The total quantity of catalysts in the TPUs is generally
about 0 to 5% by weight, preferably from 0.0001 to 1% by weight,
and particularly preferably from 0.0002 to 0.5% by weight.
[0069] It is moreover also possible to add auxiliaries and/or
additional substances during any of the steps of the process of the
invention. Mention may be made by way of example of lubricants, for
example tatty acid esters, metal soaps of these, fatty acid amides,
fatty acid ester amides, and silicone compounds, antiblocking
agents, inhibitors, stabilizers with respect to hydrolysis, UV or
other light, heat, and discoloration, flame retardants, dyes,
pigments, inorganic and/or organic fillers, and reinforcing agents.
Reinforcing agents are in particular fibrous reinforcing materials,
e.g. inorganic fibers, where these are produced in accordance with
the prior art and can also have been treated with a size.
Information in greater detail concerning the auxiliaries and
additional substances mentioned can be found in the technical
literature, for example in the monograph by J. H. Saunders and K.
C. Frisch "High Polymers", volume XVI, Polyurethane, Parts 1 and 2,
Verlag Interscience Publishers 1962 and 1964, and Taschenbuch fur
Kunststoff-Additive [Plastics additives handbook] by R. Gachter and
H Muller (Hanser Verlag Munich 1990), or DE 29 01 774 A.
[0070] Other additions that can be incorporated into the TPUs are
thermoplastics, for example polycarbonates and
acrylonitrile/butadiene/styrene terpolymers (ABS). It is also
possible to use other elastomers, for example rubber,
ethylene/vinyl acetate copolymers, styrene/butadiene copolymers,
and also other TPUs. Other compounds suitable for incorporation are
commercially available plasticizers, for example phosphates,
phthalates, adipates, sebacates, and alkylsulfonates.
[0071] For the production of the thermoplastic polyurethane in the
process of the invention, components A) and B) can preferably be
reacted in a first step, optionally in the presence of catalysts
F), at a temperature that is preferably from 100 to 250.degree. C.,
particularly preferably from 100 to 220.degree. C., to give an
NCO-terminated prepolymer.
[0072] Selection of the quantities of the reaction components for
the formation of prepolymer in the first step is preferably such
that the molar ratio of the isocyanate groups from A) to the groups
in B) reactive toward isocyanate is from 1.1:1 to 5:1, particularly
from 1.1:1 to 4:1, and particularly from 1.1:1 to 3.5:1.
[0073] It is preferable here that the components are mixed
intimately with one another, and that the prepolymer reaction is
preferably in essence carried out to full conversion, based on the
polyol component. Full conversion can be checked via titration of
the NCO content.
[0074] In a second step in the invention, the NCO-terminated
prepolymer is then reacted with the components C) chain extender
and optionally D) chain terminator, and E) other organic
diisocyanate, optionally in the presence of F) catalysts. In one
preferred embodiment of the invention, the NCO-terminated
prepolymer is then reacted only with the components C) chain
extender and optionally D) chain terminator, and E) other organic
diisocyanate, optionally in the presence of F) catalysts.
[0075] It is preferable here that the reaction temperatures
selected are the same as those for the production of the
prepolymer. However, it is also possible to select the reaction
temperatures and reaction times freely, as required by the
reactivity of the chain extender. It is preferable to continue the
reaction until the maximum possible stirrer torque is reached, and
the reaction melt can then preferably be poured onto a metal sheet
and then conditioned for a certain time, for example from 30 to 120
minutes, with a certain temperature range, from example from 80 to
120.degree. C. After the resultant TPU sheets have cooled, they can
be chopped and granulated. The resultant granulated TPU material
can then be processed by thermoplastic route, e.g. in an
injection-molding machine.
[0076] The TPUs can be produced either batchwise or continuously.
The best-known industrial production processes used for this
purpose are the mixing-head-belt process (GB 1 057 018 A) and the
extruder process (DE 1 964 834 A, DE 2 059 570 A, and U.S. Pat. No.
5,795,948 A).
[0077] The known mixing assemblies are suitable for the process of
the invention for the production of TPU, preference being given to
those operating with high shear energy. For the continuous
production process mention may be made by way of example of
co-kneaders, preferably extruders, for example twin-screw extruders
and Buss kneaders.
[0078] In one preferred embodiment of the invention, the reaction
of the components takes place in a reactive extruder or by the
mixing-head-belt process.
[0079] The process of the invention can by way of example be
carried out in a twin-screw extruder by producing the prepolymer in
the first part of the extruder and then adding the chain extenders
C), and also optionally components D) and E), in the second part.
It is possible here to add the chain extender in parallel with
components D) and E) into the same metering aperture of the
extruder, or preferably to add these in succession into separate
apertures. It is also possible that various chain extenders C) are
metered into the system in the form of a mixture, in parallel or at
separate metering apertures.
[0080] However, it is also possible to produce the prepolymer
outside of the extruder in a separate, upstream prepolymer reactor,
batchwise in a tank or continuously in a tube with static mixers,
or in a stirred tube (tubular mixer).
[0081] However, it is also possible to use a mixing apparatus, e.g.
a static mixer, to mix the chain extender and optionally components
D) and E) with a prepolymer produced in a separate prepolymer
reactor. This reaction mixture is then preferably, by analogy of
the known belt process, applied continuously to a support,
preferably a conveyor belt, where it is allowed to react until the
material solidifies to give the TPU, optionally with heating of the
belt.
[0082] The invention further provides a thermoplastic polyurethane
elastomer obtainable by the process described above of the
invention.
[0083] The invention further provides the use of the thermoplastic
polyurethane elastomers produced by the process of the invention
for the production of injection-molded or extruded items, and also
the actual items that are objects of the invention produced via
injection molding or extrusion.
[0084] The parts produced from the TPUs of the invention harden
rapidly when processed by injection molding, and therefore have
good demoldability. The injection-molded parts have high
dimensional stability and are very heat-resistant.
[0085] The TPUs of the invention can be used for the production of
a very wide variety of useful parts appropriate to their level of
hardness, for example for the production of soft, flexible
injection-molded parts, for example shoe soles, grip recesses,
sealing parts, and dust caps, and also for harder parts, for
example rollers, conveyor belts, ski boots, etc. Combination with
other thermoplastics gives products with attractive grip feel
(hard-soft combination).
[0086] The materials can also be used to produce extruded items,
e.g. profiles, films, foils, and hoses.
[0087] The examples below will provide further explanation of the
invention:
EXAMPLES
[0088] The following methods were used to characterize the
polymeric polyols used:
[0089] The CO.sub.2 content incorporated within the polyether
carbonate polyols was determined by means of .sup.1NMR (Bruker, DPX
400, 400 MHz; pulse program zg30, delay d1: 5 s, 100 scans). In
each case the sample was dissolved in deuterated chloroform.
Internal standard added to the deuterated solvent comprised
dimethyl terephthalate (2 mg for every 2 g of CDCl.sub.3). The
relevant resonances in the .sup.1H NMR (based on CHCl.sub.3=7.24
ppm) are as follows:
[0090] Carbonates, resulting from carbon dioxide incorporated
within the polyether carbonate polyol (resonances at from 5.2 to
4.8 ppm) PO not consumed in the reaction with resonance at 2.4 ppm,
polyether polyol (i.e. without incorporated carbon dioxide) with
resonances at from 1.2 to 1.0 ppm.
[0091] The molar content of the carbonate incorporated within the
polymer, of the polyether polyol fractions, and also of the PO not
consumed in the reaction are determined via integration of the
corresponding signals.
[0092] All of the number-average molar masses M.sub.n stated in the
description and in the examples for the polymeric polyols were
determined as follows: the OH number was first determined
experimentally via esterification followed by back-titration of the
excess esterification reagent with standard alcoholic potassium
hydroxide solution in accordance with DIN 53240-2. The OH number is
stated in mg KOH per gram of polyol. The number-average molar mass
can be calculated from the OH number by way of the following
formula: number-average molar mass M=56.times.1000.times.OH
functionality/OH number. The present examples assume OH
functionality F to be approximately 2.0.
[0093] In the case of low-molecular-weight polyols with defined
structure, the molar mass is calculated from the molecular
formula.
Production of TPUs 1 to 7
Stage 1)
[0094] The appropriate polyol (at 190.degree. C.) and the
diphenylmethane 4,4'-diisocyanate (MDI) at 60.degree. C. were
reacted, with stirring, as in table 1 in a reaction vessel. In all
of the examples 1 to 18 the reaction was catalyzed with 20 ppm
(based on the polyol) of Tyzor.RTM. AA 105 (Dorf Ketal) (except in
the case of examples 17 and 18; these used 50 ppm of
Desmorapid.RTM.SO from Bayer Material Science AG, Leverkusen
(tin(11) 2-ethylhexanoate)). In all of the experiments, concomitant
use was also made of 1% of Licowax.RTM. C (Clariant) as
mold-release agent (except in the case of examples 17 and 18; these
used 0.3% by weight of Loxiol.RTM.3324 from Emery Oleochemicals,
Dusseldorf) and 0.3% by weight of Irganox.RTM. 1010 (BASF SE) as
antioxidant. The reaction mixture reached a temperature maximum
(prepolymer formation). After about 60 sec. of reaction time, the
procedure was continued with stage 2. Operations in examples 19 to
21 were analogous to those of example 17, but without catalyst and
additionally with 0.045% by weight of Wacker.RTM.AK1000 silicone
oil from Wacker Chemie AG and 0.185% by weight of
Tinuvin.RTM.PUR866 from BASF SE.
Stage 2)
[0095] The 1,4-butanediol, heated to 60.degree. C., was added in
one portion to the prepolymer mixture of stage 1, and incorporated
by mixing with vigorous stirring. After about 10 to 15 seconds, the
reaction mixture was poured onto a coated metal sheet and subjected
to postconditioning at 80.degree. C. for 30 minutes, After cooling,
this gave a cast TPU sheet.
Production of TPU 8 with the Molar Data of Table 1
Stages 1 and 2
[0096] A prepolymer was produced from polyol No. 2 and MDI as in
examples 1 to 7. The resultant prepolymer was then further reacted
with polyol No. 1 and 1,4-butanediol. The reaction mixture was
poured onto a coated metal sheet and subjected to postconditioning
at 80.degree. C. for 30 minutes. After cooling, this gave a cast
TPU sheet.
[0097] Table 1 describes the components used, and proportions
thereof, for the production of the TPUs.
TABLE-US-00001 TABLE 1 Molar proportions of the starting components
for the synthesis of the TPUs Polyol MDI 1,4-Butanediol Example
Polyol No. [mol] [mol] [mol] 1* 1 1 4 3 2 2 1 4 3 3* 3 1 4 3 4 4 1
6.6 5.6 5* 5 1 6.6 5.6 6* 1 and 5 0.5 + 0.5 5.3 4.3 7 6 1 5.3 4.3 8
2 and 1 0.67 + 0.33 4 3 *comparative example not of the
invention
[0098] Polyol 1: Acclaim.RTM.2200 (polypropylene oxide glycol with
OH number 56.7 mg KOH/g (M.sub.n=1979 g/mol, from Bayer
MaterialScience AG).
[0099] Polyol 2: Polyether carbonate diol based on propylene oxide
and CO.sub.2 with OH number 58.2 mg KOH/g (M.sub.n=1928 g/mol) and
with 15.1% by weight incorporated CO.sub.2 content.
[0100] Polyol 3: Polyether carbonate diol with OH number 60.9 mg
KOH/g (M.sub.n=1842 g/mol) obtained via reaction of a polypropylene
oxide glycol with OH number 522 mg KOH/g with diphenyl carbonate
with elimination of phenol.
[0101] Polyol 4: Polyether carbonate diol based on propylene oxide
and CO.sub.2 with OH number 28.5 mg KOH/g (M.sub.n=3937 g/mol) and
with 19.0% by weight incorporated CO.sub.2 content.
[0102] Polyol 5: Acclaim.RTM.4200 (polypropylene oxide glycol with
OH number 28.9 mg KOH/g (M.sub.n=3882 g/mol, from Bayer
MaterialScience AG).
[0103] Polyol 6: Polyether carbonate diol based on propylene oxide
and CO.sub.2 with OH number 37.7 mg KOH/g (M.sub.n=2976 g/mol) and
with 17.5% by weight incorporated CO.sub.2 content.
Studies on TPUs 1 to 8:
[0104] The resultant cast TPU sheets were chopped and granulated.
The granulated material was processed in an Arburg Allrounder 470S
injection-molding machine in a temperature range from 180 to
230.degree. C. and in a pressure range from 650 to 750 bar with an
injection flow rate of from 10 to 35 cm.sup.3/s to give bars (mold
temperature: 40.degree. C.; bar size: 80.times.10.times.4 mm) and
sheets (mold temperature: 40.degree. C.; size: 125.times.50.times.2
mm).
[0105] The following test methods were used:
[0106] Hardness was measured in accordance with DIN 53505, abrasion
was measured in accordance with DIN ISO 4649-A, and the tensile
test was carried out in accordance with ISO 37.
[0107] Dynamic mechanical analysis (DMA: storage-tensile modulus of
elasticity):
[0108] Rectangles (30 mm.times.10 mm.times.2 mm) were punched out
from the injection-molded sheets. These test sheets, under constant
preload--where appropriate dependent on the storage modulus--were
subjected to periodic excitation with very small deformations, and
the force acting on the clamp system was measured as a function of
the temperature and excitation frequency.
[0109] The preload additionally applied serves to retain adequate
clamping of the sample when deformation amplitude is negative.
[0110] The DMA measurements were taken using a Seiko DMS 210 at 1
Hz in the temperature range from -150.degree. C. to 200.degree. C.
with a heating rate of 2.degree. C./min.
[0111] The behavior of the invention under warm conditions was
characterized by measuring and stating the storage-tensile modulus
of elasticity at +20.degree. C. and at +60.degree. C., for
comparison.
[0112] Heat resistance is characterized by stating the temperature
at which the value is less than 2 MPa, i.e. the injection-molded
part no longer retains a stable shape. The higher the temperature
value, the more stable the TPU.
[0113] Table 2 describes the properties determined for the TPUs 1
to 8.
TABLE-US-00002 TABLE 2 Results Example 1* 2 3* 4 5* 6* 7 8
Immediate hardness [Shore A] 83 85 90 75 64 74 82 86 Abrasion
[mm.sup.3] 83 38 132 207 249 180 139 71 100% modulus [MPa] 6.4 9.7
11.9 4.9 3.0 4.3 7.0 7.8 300% modulus [MPa] 10.3 15.9 14.7 7.9 5.5
7.5 11.3 12.3 Tensile strength [MPa] 22.2 32.2 16.9 10.4 8.0 12.6
19.3 24.1 Tensile strain value [%] 651 553 496 775 793 857 649 596
DMA measurement: Modulus of elasticity (20.degree. C.) [MPa] 26 120
51 18 6 10 32 33 Modulus of elasticity (60.degree. C.) [MPa] 17 31
18 10 5 9 16 18 T (2 MPa) [.degree. C.] 139.3 145.3 137.2 119.8
110.8 120.1 136.8 143 *comparative example not of the invention
[0114] When the TPUs of the invention from examples 2 and 8 are
compared with the respective examples (1 and 3) not of the
invention, they have similarly high hardness by virtue of the
identical molar quantity of chain extender and therefore hard
segments. The TPUs of the invention from examples 2 and 8 moreover
have a markedly better level of mechanical properties than the
respective comparative products (examples 1 and 3), this being
particularly apparent from the tensile strength. The abrasion
values of the TPUs of the invention from examples 2 and 8 are
likewise markedly lower than the abrasion values of the comparative
TPUs.
[0115] The two other TPUs of the invention from examples 4 and 7
also have a better level of mechanical properties and better
abrasion values than the respective comparative examples 5 and
6.
[0116] The modulus of elasticity value measured by DMA at
.+-.20.degree. C. and at +60.degree. C. are markedly higher for
examples 2, 4, 7, and 8 of the invention than for the corresponding
comparative examples 1, 3, 5, and 6, as also is the temperature at
which a minimum stress of 2 MPa is retained. At high temperatures,
the TPUs of the invention are therefore markedly more
heat-resistant than the comparative TPUs.
[0117] Table 3 below describes the components used, and proportions
thereof, for the production of TPU 9 to TPU 21.
TABLE-US-00003 TABLE 3 Molar proportions of the starting components
for the synthesis of the TPUs Polyol MDI 1,4-Butanediol Example
Polyol No. [mol] [mol] [mol] 9* 1 1 4.08 3 10 7 1 4.08 3 11 8 1
4.08 3 12 1 and 7 0.1 + 0.9 4.08 3 13 1 and 7 0.25 + 0.75 4.08 3 14
1 and 7 0.5 + 0.5 4.08 3 15 1 and 7 0.75 + 0.25 4.08 3 16 1 and 7
0.9 + 0.1 4.08 3 17* 9 1 2.35 1.3 18 9 and 11 0.67 + 0.33 2.35 1.3
19* 9 and 10 0.67 + 0.33 7.36 6.22 20 11 and 10 0.67 + 0.33 7.36
6.22 21 9 and 7 0.67 + 0.33 7.36 6.22 *comparative example not of
the invention
[0118] Polyol 7: Polyether carbonate diol based on 1,2-propanediol,
propylene oxide and CO.sub.2 with OH number 55.5 mg KOH/g
(M.sub.n=2022 g/mol) and with 18.8% by weight incorporated CO.sub.2
content.
[0119] Polyol 8: Polyether carbonate diol based on 1,2-propanediol,
propylene oxide and CO.sub.2 with OH number 59.8 mg KOH/g
(M.sub.n=1876 g/mol) and with 24.7% by weight incorporated CO.sub.2
content.
[0120] Polyol 9: Terathane.RTM. 1000, polytetramethylene glycol
from Invista with OH number 114,4 mg KOH/g, (M.sub.n=981
g/mol).
[0121] Polyol 10: Terathane.RTM. 2000, polytetramethylene glycol
from Invista with OH number 55.0 mg KOH/g (M.sub.n=2040 g/mol).
[0122] Polyol 11: Polyether carbonate diol based on
1,2-propanediol, propylene oxide and CO.sub.2 with OH number 115.5
mg KOH/g (M.sub.n=971 g/mol) and with 15.4% by weight incorporated
CO.sub.2 content.
[0123] The TPUs produced from examples 9 to 21 were processed as
described above examples 1 to 8), and the mechanical properties
were determined. The values found are listed in table 4 below.
TABLE-US-00004 TABLE 4 Results of examples 9 to 21 TPU Tensile from
Hardness 100% 300% Tensile strain example [Shore modulus modulus
strength value No. A/D] [MPa] [MPa] [MPa] [%] 9* 83A 5.0 8.4 16.8
729 10 88A 10.4 17.3 35.5 583 11 94A 16.0 24.1 34.2 506 12 82A 8.3
14.6 31.0 586 13 84A 7.7 13.4 32.4 610 14 83A 6.6 11.7 27.8 621 15
84A 6.5 11.5 27.4 623 16 84A 6.2 11.2 28.1 625 17* 86A 7.4 15.9
38.2 417 18 85A 7.6 14.7 38.8 474 19* 66D 31.1 -- 36.2 219 20 72D
35.6 44.8 45.3 308 21 69D 32.5 41.6 41.6 310 *comparative example
not of the invention
[0124] When the TPUs of the invention from examples 10 and 11 are
compared with the comparative TPU from example 9, they have higher
hardness and markedly higher mechanical strength values (modulus
values and tensile strength). Although the tensile strain value is
somewhat smaller than for the TPU from example 9, it remains very
good: above 500%.
[0125] When the TPUs of the invention from examples 12 to 16 are
compared with the comparative TPU from example 9 they have
similarly high hardness, but a markedly higher level in mechanical
properties (modulus values and tensile strength) with very good
tensile strain value, although the quantity of polyether carbonate
diol used concomitantly in test 16 was only 10 mol %.
[0126] When the TPUs of the invention from example 18 is compared
with the comparative TPU from example 17 it has comparable hardness
and an almost identical level of mechanical properties, but the
tensile strain value of the TPU of the invention is markedly
better.
[0127] When the TPUs of the invention from examples 20 and 21 are
compared with the comparative TPU from example 19, they have
somewhat higher hardness, but a markedly higher level of mechanical
properties (modulus values and tensile strength), and also a
markedly higher tensile strain value.
* * * * *